Railway electric signal system



May 24 1932- E. J. QUINBY 1,859,466

RAILWAY ELECTRIC SIGNAL SYSTEM Filed Feb. l, 1930 f INVENTOR E j EDWIN JAY aulNY l: I 3 BY r: I :x ,7 /LO'VVL/ ATTORNEY Patented May 24, 1932 narran s'rATEs EDWIN JAY QUINBY,

OF YONKERS, NEW' YORK, ASSIGNOR TO RADIO CORPORATIONOF AMER-IGA, A CORPORATION OF DELAWARE c RAILWAY ELECTRIC SIGNAL SYSTEM porated in existing installations and which l has comparatively low initial and maintenance cost.

An 'object of the invention is to provide a novel and efficient railway signal system having no moving parts.

Another object of the `invention is to provide a railway signal system in which no interconnecting wires are required.

Another object of the invention is to provide a' railway signal system in which signal target'lamp failure in any signal target will not leave the corresponding block unprotected, but rather will give visible indication that lamp replacement is necessary.. n

Another object of the invention is to provide an electric railway signal system which may be used for one way or two way operation on the same track. f Y

A further object of the invention is to provide an electric railway signal system which protects trains entering or leaving ajblo'ck in eitherdirection. e f y Y Still another object of the invention is-to provide an electric railway signal' system which protects any number of trainsections having rights in the same block until all'have left the block.

Another object of the' invention isto provide an electric railway signal system which may be used to indicate at a central point the condition of a block. Y ,Y

Other objects and advantages of the invention will be apparent to those skilled in the art from reading the following detailed specification.

It is well knownthat the block signal systems as at present employed in railway work are very complicated and-'are subject to failure with the result that accidents in which human life is lost area commonoccurrence. The failure of signal systems as now employed is undoubtedly due to the'great number of movingVV parts which are employed to make up the system. It can, therefore, be seen that'while a railway signal system with few moving parts is greatly desired, ai railway Application filed February 1, 193D. Serial No. 425,109.

signal systemwith no moving parts whatever is the great desideratum.

To this` end this invention embodies a` in electric, steam and *internal combustion, types of railway practice as well as in any otherA type which utilizesv rails as the roadway.

The inventionwill be set forth in the following detailed description taken inconnection with the accompanying drawings in which: j

Figure 1 illustrates the invention as applied to a long length of track in which sieveral blocksare shown; and,

'1 Figure 2 illustrates diagrammatically a` A crosssection throughthe tracks ata signal pointand `theconnections vof the two rails to the signal proper.

Referring toFigure l of the drawings,

1, and 2 illustra-teV the two rails of a tracklr 'Rail 2 is' constructed'so as to'be electrically continuous, whereas rail l is divided into blocks of convenient lengths electrically insulated from one another as is common inthe railway signal art. vIn the drawings three blocks A, B and Care shown insulated from eachv other at the points 3 and'fl. The systemas illustrated in Figure 1 covers the case where a single track` is used fortwo wayl traffic which for convenience will beV called'V westbound and eastbound. In such an inblock againstboth eastboundand westbound trains.` For this purpose at the west end of each block arsignal target must be placedI facing west so as to protect that block against eastbound trains and at theeast end of each block a signal target must be placed facing east to protect that block againstrg l westbound trains'. A Signaltargetsso placedare shownbyy, 7 and 8 in Fig. l.

get reference 4willy-now `be had to Fig.'` 2,

For avdetailed discussion of thelsignal tar.- A

-wherein 1l representsfa cross-'section of thetr" v lamps 9 and l() is in series with respect to the rail arranged in insulated blocks and 2 represents a cross-section of the electrically continuous rails.

The signal target 6 comprises three lamps 9,10 and l1 of which 9 and l0 are preferably red and l1 is green. A source of current l2 is adapted to supply current for said lamps 9, l0 and 11. rEhe two red lamps, namely 9 and l0, are arranged in parallel and the circuitcomprising the two parallelly connected source l2 with lamp l1. lIt will thus be evident that current from source l2` must of necessity vHow partly through 9vand partly through 19 whereas all of it flows through 11. An electrical conductor 14 .connects one side of lamp ll to rail l, and a conductorl connects the other side' of lamp l1 with rail 2. A portion ofvone truck of acar is diagrammatically illustrated rand generally represented as 13.

The'truck must be so constructed 'as to forman electrical conducting path between rails l .and In other words when a car enters a certain block .lamp l1 must be shortcircuited by conductor l5, rail 2,'truck 13,

rail l and conductor 14; with the result .that

not enough Ycurrent Hows through lamp llto light it. Y

The various resistances of the lamps .and track must be so chosen that when lamp' ll is not `short-circuited not enough current flows through either of lamps `9 and 170t'o light Vthem whereas the `sum .of the currents passing `through 9v and 10 is suiiicient tolight up lamp ll. Y. Y Y

However, when lamp 1l is short-circuited enough current will flow through both lamps 9 and 10 to light them both. A

Thevdevice operates as follows :`V A .train in agiv-en block short-circuits the `one green lamp in each .of the signals pro- V tecting :this block .thus extinguishing these green lamps but providing-a direct path vfor the `flow of current from the source 1 2 of each f signal target to light up the ,two red lamps connected in-parallelV in each signal. l

fVVhen the trainleaves the block the short- Ycircuitfcausedby the wheels and axles `of. the train across the rails `no longer leXists and thergreen 'lamp in each signal is Vagain lighty.ed by the-.current which flows through .the

double'path Yaffordedvby the .two .red lamps in Yparallel. In this latter-caseythe ii-lamentsfof :the :red ylamps .pass sufficient current to :illuminate .the Ysinglegreenf' lamp, although .the

filamentof the red lamps do Vnot'heatnp -suiii- Yciently .to cause a visible glow.: Y kT-husfwhen there .is no tnainV in the block eachjsignalprotecting that block indicates fclearby show- `ing-one green llight whereas .when the .block y is occupied by a train cach -offthe-signals Yprotectingy that block 1indicates danger by means ofy two :red lights. y, -f if Of course, the-color combi-nationv maybe `simple and cheap construction. Vadditionallamps :may be'connected in parf arranged as desired and the signals may be arranged to give the necessary indications by means of lamp positions rather than lamp colors or by both.

It will be noted that for one way operation of ,traflic onlyy one signal is necessary which signal is placed at the entrance of each block and it faces against traflic direction.

An advantage of my device is that a visual indicationasto whether the signalis operative is always had.'v Thus if a red lamp has burned out both red and green lights will be on when' the block is unoccupied;V if the greenglight burns out then no lights will be on unless a train is in the block in whichy case the `red lights will be .onand the Yblock protected.; if both redV lamps are burned out then no lights willbe on at any timegand lastly if .all three are burned out` no indication Vwill be give-ni` VThe failure of any single lamp-in r a signalA does not leave the block -unprotected, vbut does give indication of the necessi- Asignal-solely for the purpose of simplifying the descriptionV and that a single source .and/or any power supply network as for instance alternating or direct current genera- 1 tors may be Vemployed lwithout in any way afi' fecting the" invention.

The. .invention as herein Vdescribed showsV the least number `of lamps advisable for However,

al-lel to 'augment these lamps, thus, reducing the possibility of lamp vfailures effecting the indicating'and adding to the-factor ofsafety. 'In 'i'this `case the ratio of 2 vto l for red and green should be maintained. This invention may be embodied in other :forms without depart-ngin any wise from the spiritoffthis invention thel scope of which is deiined'in the appended claims. Y

. claim:y

l. In a railway signalling system, .an insulated block section','means for indicating thev condition of said block comprising aclear signal indicator, an occupied signalvindicator and a current source all thereof forming a' series circuit whereby lthe i other indicatoriis rendered operativel` 2. Ina. railwayY signalling system,"an in- 'y sulated block section, a clear signal indicator devi-ce :and an occupied signal indicator device therefor, a Vsourceof currentffor said,V

-indicatordevicea said indicator devices and said .source being arranged all electrically in serlesfthe resistances of saidindicator devices being's'o chosen that-only one of said indicator devices is affected perceptibly when currentfrom said source is flowing through both, and means when said block section is y Occupied for rendering said last mentioned indicator device inoperative and thereby reducing the resistance of said series circuit whereby the other indicator device becomes operative.

3. In a railway signalling system an insulated block section, a clear and occupied signal indicator device at each end thereof, a source of current for each of said devices, each of said indicator devices comprising a clear signal indicator and an occupied signal indicator both arranged electrically in series with the said source of current and with each other, the resistances o' said indicator device being so chosen that only one thereor` is affected perceptibly when current trom said source is flowing through both, and means when said block section is occupied for short-circuiting the indicator affected when current is flowing through both whereL by said indicator is rendered inoperative and the other indicator device is rendered operative.

4. In a device for indicating the condition of an insulated block section of a railway system, a circuit comprising an occupied signal indicator device, a clear signal indicator device and a source of current all electrically in series, the respective resistances of said indicator devices being so chosen that only said clear signal indicator device is aiected sufficiently so as to be perceptible when current from said source is flowing through both, and

means for short-circuiting said clear signal indicator device whereby the resistance of said circuit is reduced to such an extent that Vsaid occupied signal indicator device is rendered operative.

5. In an electrical railway signalling device a clear signal indicator and an occupied signal indicator said occupied signal indica-v tor comprising a plurality of parallel paths, and a current source, said indicators and current source being arranged all-electrically in series, the resistance of said clear signal indicator device being so chosen that if sh0rtcircuited the resistance of the series lcircuit is so reduced that ythe occupied signal indicator device is rendered operative.

6. In a railway signalling system an insulated block section, a clear signal indicator Y device and an occupied signal indicator device therefor, a source of current for said indicator device said source of current and indicator devices being arranged all electrically in series, said occupied signal indicator comprises a -plurality of parallel paths for passing current from said source, and means when said block section is occupied for shortcircuiting the clear signal indicator device, the resistance of the circuit comprising the source and the two indicator devices in series being so Y chosen ,that not enough current passes through any offsaid above mentioned parallel branches to aiect the occupied signal indicator but enough current passes through the clear signal indicator device for aiecting it and when said clear Vsignalindicatoris short-circuited the resistance Vof said above mentioned circuit is so reduced that enough current passes through the occupied signal indicator for perceptibly affecting it.

7. In a device for indicating the condition oi a block section in a railway system, a circuit coniprising an occupied signal indicator device, a clear signal indicator device and a source of direct current all electrically in series, the respective resistance of said indicator devices being so chosen that only said clear signal indicator device is affected suiiiciently to be perceptible when current from said source is flowing through both said indicator devices, and means including the rails of said railway system for short-circuiting said clear signal indicator device whereby the resistance of said circuit is reduced to such an eX-A EDWIN JAY QUINBY.'

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